Genesis

I know this is not a scientific or "in water" test but for grins and giggles while playing with the K1 on the couch early on I tried breathing it with no scrubber media in the can at all.

Within a minute or two of starting I got VERY lightheaded and, well, "weird". There was breath hunger (which of course isn't sated by breathing faster!) but there were also what could only be described as coordination and mental deficits that started to snowball FAST.

I dropped the mouthpiece, but if I hadn't (or turned it to OC) I suspect I would have passed out.

Had plenty of O2 (setpoint control was running) but of course way too much CO2.

Underwater I can easily see where that could kill you almost without warning. I'm not sure that if I was finning hard against a current or otherwise preoccupied that I would recognize the incipient symptoms until my coordination and mental faculties were severely compromised, and at that point I'm not certain I could successfully bail if I had to swap mouthpieces. I DID have enough left to turn the knob.

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